title: Arachidonic acid metabolism in the neonatal platelet.
abstract: An assessment of arachidonic acid metabolism in the platelet of the neonate was performed. The uptake of [14C]arachidonic acid into platelets of both the neonate and the adult were similar. Neonatal platelets, however, released a significantly greater amount (P less than .001) of prelabeled arachidonic acid (24.7% +/- 2.8%) in response to the physiologic agent thrombin when compared with platelets from adult control subjects (14.6% +/- 0.8%). When the activities of the lipoxygenase (12-L-hydroxy-5,8,10,14-eicosatetraenoic acid) and cyclooxygenase pathways (12-L-hydroxy-5,8,10-heptadecatrienoic acid and thromboxane B2) were evaluated following incubation of platelets with [14C]arachidonic acid, significant differences were observed between adult and neonatal platelets. Platelets from the neonate produced less (P less than .01) thromboxane B2 (11.1% +/- 1.7%) when compared with platelets from adult control subjects (19% +/- 1.7%). In contrast, the lipoxygenase product 12-L-hydroxy-5,8,10,14-eicostatetraenoic acid was increased (P less than .005) in the platelet from the neonate (41.5% +/- 2%), when compared with the adult (31.2% +/- 2.1%). The observation that the availability of substrate arachidonic acid is increased in the platelet of the neonate may have general implications in neonatal pathophysiologic processes.
mesh_terms: D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D000328:Adult; D000375:Aging; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000097:blood*; D001792:Blood Platelets / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000097:blood; D006801:Humans; D006880:Hydroxy Acids / Q000097:blood; D066298:In Vitro Techniques; D007231:Infant, Newborn; D008084:Lipoxygenase / Q000097:blood; D011451:Prostaglandin-Endoperoxide Synthases / Q000097:blood; D013929:Thromboxane B2 / Q000097:blood
chemical_list: D001095:Arachidonic Acids; D005231:Fatty Acids, Unsaturated; D006880:Hydroxy Acids; D016718:Arachidonic Acid; C008033:12-hydroxy-5,8,10-heptadecatrienoic acid; D013929:Thromboxane B2; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D008084:Lipoxygenase; D011451:Prostaglandin-Endoperoxide Synthases